MONDAY, Feb. 8 (HealthDay News) -- High blood pressure may predict dementia in older adults with impaired executive function (difficulty organizing thoughts and making decisions), but not in those with memory problems, a new study has found.

The study included 990 dementia-free participants, average age 83, who were followed-up for five years. During that time, dementia developed in 59.5% of those with and in 64.2% of those without high blood pressure. Similar rates were seen in participants with memory dysfunction alone and with both memory and executive dysfunction.

However, among those with executive dysfunction alone, the rate of dementia development was 57.7% among those with high blood pressure compared to 28% for those without high blood pressure, which is also called hypertension.

"We show herein that the presence of hypertension predicts progression to dementia in a subgroup of about one-third of subjects with cognitive impairment, no dementia," wrote the researchers at the University of Western Ontario in Canada. "Control of hypertension in this population could decrease by one-half the projected 50-percent five-year rate of progression to dementia."

The study findings are published in the February issue of the journal Archives of Neurology.

The findings may prove important for elderly people with cognitive impairment but no dementia, the study authors noted.

"Worldwide, neurologic disorders are the most frequent cause of disability-adjusted life years; among these, cerebrovascular disease is the most common risk factor, and dementia is the second most common. There is no preventive or therapeutic intervention to mitigate this public health burden," the researchers wrote.